Electronic units for motor vehicles that are positioned outside the vehicles are subjected to environmental stresses such as cold and ice. In order that they are not subjected to lasting effects of these stresses, these electronic units are generally equipped with electrical devices that make it possible to clear the effects of these stresses. There may be found, for example, electronic units equipped with electrical devices such as for example heating elements to combat frost. These electrical devices are generally controlled by way of wiring harnesses and connectors linking an electronic control board to the electrical devices. The current solutions for the electrical connection of these electrical devices are bulky, expensive and cumbersome.